Since the particular digital frame my hubby got me doesn't have any hard drive in it and uses a memory card which has to be in it for it to run, I assume it will hold as many pictures as on the memory card. Before I downloaed them onto my computer, it had 189 pics on it. You set the frequency for the pictures to change, anywhere from 10 seconds to 30 minutes. It can be a slide show or random. And you can put music on it. So if my son in law over in Iraq had one, we could send a memory card of like a wedding and have the wedding music on it or a birthday theme. Get the 'picture'?

I fugured out that the SD slot on my GPS is also a memory slot. I can put pictures or music on it. Now why I would want pictures or music on my GPS unit I don't know.